/* {{{ License.
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *///}}}

// :indentSize=4:lineSeparator=\n:noTabs=false:tabSize=4:folding=explicit:collapseFolds=0:

package org.mathpiper.lisp;

import org.mathpiper.lisp.cons.ConsPointer;

/**
 * Value of a Lisp global variable. The only special feature of this class is
 * the attribute <b>iEvalBeforeReturn</b>, which defaults to <b>LispFalse</b>.
 * If this attribute is set to <b>LispTrue</b>, the value in <b>iValue</b> needs
 * to be evaluated to get the value of the Lisp variable. See:
 * LispEnvironment::GetVariable()
 */
class GlobalVariable {
  ConsPointer iValue = new ConsPointer();
  boolean iEvalBeforeReturn;

  protected GlobalVariable(ConsPointer aValue) {
    iValue.setCons(aValue.getCons());
    iEvalBeforeReturn = false;
  }
  public GlobalVariable(GlobalVariable aOther) {
    iValue = aOther.iValue;
    iEvalBeforeReturn = aOther.iEvalBeforeReturn;
  }
  public ConsPointer getValue() {
    return iValue;
  }

  public boolean isIEvalBeforeReturn() {
    return iEvalBeforeReturn;
  }

  public void setEvalBeforeReturn(boolean aEval) {
    iEvalBeforeReturn = aEval;
  }

  @Override
  public String toString() {
    return iValue.getCons().toString();
  }

}
